title: Interaction of oxygen with Au/Ti(0001) surface alloys studied by photoelectron spectroscopy.
abstract: The interaction of oxygen with gold adsorbed on Ti(0001) was studied by synchrotron radiation photoelectron spectroscopy. Two kinds of surfaces were explored: as-deposited 0.38, 1.16 and 1.85 monolayer (ML) thick Au overlayers on the Ti(0001) surface, and the same samples after thermal treatment, which resulted in the formation of Au-Ti intermetallic surfaces. The Ti 3p core level was strongly affected by reaction with oxygen, while the Au 4f core level showed only minor changes other than a decrease in intensity. The Ti 3p peak was fitted with several components which were identified as Ti atoms in different oxidation states, namely TiO, Ti(2)O(3), TiO(2) and Ti-OH. Titanium oxide phase formation is accompanied by Au-Ti bond dissociation and outward diffusion of Ti. The presence of an Au-Ti intermetallic phase on the Ti(0001) surface promotes oxidation of the Ti atoms.
authors.affiliation: Faculty of Mathematics and Physics, Department of Surface and Plasma Science, Charles University, V Holešovičkách 2, 18000 Prague 8, Czech Republic. tsud@mbox.troja.mff.cuni.cz
authors.forename: N
authors.initials: N
authors.lastname: Tsud
authors.forename: F
authors.initials: F
authors.lastname: Šutara
authors.forename: I
authors.initials: I
authors.lastname: Matolínová
authors.forename: K
authors.initials: K
authors.lastname: Veltruská
authors.forename: V
authors.initials: V
authors.lastname: Dudr
authors.forename: K C
authors.initials: KC
authors.lastname: Prince
authors.forename: V
authors.initials: V
authors.lastname: Matolín
mesh_terms: D000327:Adsorption; D000497:Alloys / Q000737:chemistry*; D004058:Diffusion; D006046:Gold / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D056951:Photoelectron Spectroscopy / Q000379:methods*; D013499:Surface Properties; D013696:Temperature; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D010087:Oxides; C009495:titanium dioxide; D006046:Gold; D014025:Titanium; D010100:Oxygen